About Schema Wrapper Libraries (Java)
The default mapping of XML Schema types to Java data types is as follows:
XML Schema | Java | Remarks |
|---|---|---|
xs:string | String | |
xs:boolean | boolean | |
xs:decimal | java.math.BigDecimal | |
xs:float, xs:double | double | |
xs:integer | java.math.BigInteger | |
xs:long | long | |
xs:unsignedLong | java.math.BigInteger | Java does not have unsigned types. |
xs:int | int | |
xs:unsignedInt | long | Java does not have unsigned types. |
xs:dateTime, date, time, gYearMonth, gYear, gMonthDay, gDay, gMonth | ||
xs:duration | ||
xs:hexBinary and xs:base64Binary | byte[] | Encoding and decoding of binary data is done automatically. |
xs:anySimpleType | string |
All XML Schema types not contained in this list are derived types, and mapped to the same Java type as their respective base type.
Generated Classes
For each type in the schema, a class is generated that contains a member for each attribute and element of the type. The members are named the same as the attributes or elements in the original schema (in case of possible collisions, a number is appended). For simple types, assignment and conversion operators are generated. For simple types with enumeration facets, the methods GetEnumerationValue() and SetEnumerationValue(int) can be used together with generated constants for each enumeration value. In addition, the method StaticInfo() allows accessing schema information as one of the following types:
com.altova.xml.meta.SimpleType
com.altova.xml.meta.ComplexType
Classes generated from complex types include the method SetXsiType(), which enables you to set the xsi:type attribute of the type. This method is useful when you want to create XML instance elements of a derived type.
In addition to the classes for the types declared in the XML Schema, a document class (identified with "Doc" below) is generated. It contains all possible root elements as members, and various other methods. For more information about the class, see com.[YourSchema].[Doc].
Note: The actual class name depends on the name of the .xsd schema.
For each member attribute or element of a schema type, a new class is generated. For more information about such classes, see:
com.[YourSchema].[YourSchemaType].MemberAttribute
com.[YourSchema].[YourSchemaType].MemberElement
Note: The actual class names depend on the name of the schema attribute or element.
Error Handling
Errors are reported by exceptions. The following exception classes are defined in the namespace com.altova:
Class | Base Class | Description |
|---|---|---|
SourceInstanceUnvailableException | Exception | A problem occurred while loading an XML instance. |
TargetInstanceUnavailableException | Exception | A problem occurred while saving an XML instance. |
In addition, the following Java exceptions are commonly used:
Class | Description |
|---|---|
java.lang.Error | Internal program logic error (independent of input data) |
java.lang.Exception | Base class for runtime errors |
java.lang.IllegalArgumentsException | A method was called with invalid argument values, or a type conversion failed. |
java.lang.ArithmeticException | Exception thrown when a numeric type conversion fails. |
Accessing schema information
The generated library allows accessing static schema information via the following classes:
com.altova.xml.meta.ComplexType
com.altova.xml.meta.SimpleType
The properties that return one of the metadata classes return null if the respective property does not exist.